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Product Summary

A variator is a device that can change its parameters, or can change parameters of other devices. A variator is an element of the Continuously Variable Transmission commonly used on mopeds and other small engine vehicles. Motobecane, Peugeot, Derbi, Vespa, Minarelli, and Honda mopeds all offered at least one model with a Variator transmission.

Variator transmissions use centrifugal weights to decrease the engine's gear ratio as engine speed increases. This allows the variator to keep the engine within its optimal efficiency while gaining ground speed, or trading speed for hill climbing. Efficiency in this case can be fuel efficiency, decreasing fuel consumption and emissions output, or power efficiency, allowing the engine to produce its maximum power over a wide range of speeds.

Since the variator keeps the engine turning at constant RPMs over a wide range of vehicle speeds, turning the throttle grip will make the moped move faster but doesn't change the sound coming from the engine as much as a conventional two speed or one speed. This confuses some riders and leads to a mistaken impression of a lack of power.